Rotary drum type cutting and dislodging head



Oct. 12, 1954 R. c. LUNDQUIST ROTARY DRUM TYPE CUTTING AND DISLODGING HEAD Filed March 12, 1952 2 Sheets-Sheet 1 V2.5. llll: 5 3/ 2 3 J Oct. 12, 1954 R. c. LUNDQUIST 2,691,511

ROTARY DRUM TYPE CUTTING AND DISLODGING HEAD Filed March 12, 1952 2 Sheets-Sheet 2 o I o o o o o o o o 25 I o 0 0 0 39 o o 0 5 45 o o 9 KE 0 0 I 1720672307' i 152%a2u Czuna'yazsl Patented Oct. 12, 1954 ROTARY DRUM TYPE CUTTING AND DISLODGING HEAD Richard C. Lundquist, Chicago,

111., assignor to Goodman Manufacturing Company, Chicago, Ill., a corporation of Illinois Application March 12, 1952, Serial No. 276,085

8 Claims.

This invention relates to mining machines, and more particularly to a rotary cutting and dislodging head for use with a continuous mining machine, although not limited to such use.

One of the problems in mining coal from the solid face is that of dislodging the coal in sufficiently large particle sizes with a minimum of dust and fines. One object of the present invention is to provide a rotary mining head which will produce coal in desirably large particle sizes with a minimum of power consumption.

In carrying out my invention, I provide a rotary cylindrical member mounted for simultaneous rotation and swinging movement along the working face, and provided with a lurality of combined cutting and impact devices each pivotally mounted on the periphery of said rotary member so as to be supported in a relatively collapsed, coalcutting position relative to the rotary member during its portion of circumferential that is engaged positively against the working face, but being free to be swung by centrifugal force in the plane of rotation when it is released from positive engagement with the working face, to impart a hammer-like blow against the working face as it approaches the latter for the next succeeding positive engagement therewith.

As a result of my novel form of pivotally mounted, hammer-like members, the coal tends to be dislodged in larger lump sizes than with conventional pick or bit devices, and the hammer-like members also aid in breaking down the standing cores which otherwise may be left between adjacent rows of picks or bits carried on the periphery of the rotatable head.

Other objects and advantages of the invention will appear from time to time as the following description proceeds.

The invention may best be understood by reference to the accompanying drawings, in which:

Figure 1 is a fragmentary plan view, in part section of a rotary mining head constructed in accordance with my invention;

Figure 2 is a section taken on line 2-2 of Figure 1;

Figure 3 is a fragmentary sectional view, largely diagrammatic, illustrating the manner in which the rotary mining head may be mounted on a conventional mining machine and operated for removing coal from a working face;

Figure 4 is a detail section of an impact member taken on line 4-4 of Figure 2;

Figure 5 is a sectional view similar to Figure 4, but showing a modified form of hammer head for the impact member;

Figure 6 is a diagrammatic showing of one form of bit pattern produced by the impact members mounted on the rotary mining head.

Referring now to details of the illustrative embodiment of my invention shown in Figures 1 to 5, the mining head indicated generally at I0 is of the kind adapted to be substituted for the mining head of a continuous mining machine such as disclosed in an application of Frank Cartlidge, Serial Number 116,684, filed September 20, 1949. In machines of this general type, the head I 0 consists of a generally cylindrical drum rotatably supported at opposite ends between the forward ends of spaced arms or chain-carrying cutter bars H, H. The rear ends of the cutter bars I I, II are pivotally mounted to the body of the machine for swinging movement on a transverse axis indicated at 2. The cutter bars have cutter chains l3 movable orbitally thereabout, and are driven as usual by suitable power means for feeding the cutter head with an arcuate sweeping movement vertically along the working face. With my form of cutter head, the machine is pref erably operated to make its feeding cut from the top to the bottom of the working face, as is common practice with certain continuous mining machines of this general type.

For a further detailed description of the entire mining machine and its operation, reference may be made to the aforesaid application.

The rotary head [0 consists of a hollow drumli-ke portion l5 having at each end an inner telescopically assembled bearing section It welded thereto after assembly of a mounting shaft l! therewithin. The latter is secured at eachend within a collar I8 carried by one of the cutter bars I I, and is held fast to the latter by a lock nut 19.

A sprocket 2| driven by cutter chain [3 on the proximate cutter bar H is fixed on each bearing section [6 as by a key 23, and said bearing section is rotatably supported on the shaft I! as by antifriction bearings 24.

A plurality of hammer arms 25, 25 are pivotally connected at their inner ends on pivot pins 26, 26 extending between pairs of upstanding lugs 21, 21 carried on the periphery of the drum l5. For convenience in mounting the hammer arms on the drum, a plurality of detachable rings 28, 28 are mounted in side-by-side relation along the drum, each ring having three pairs of pivot lugs 21, 21 disposed at equal angles of degrees to each other.

The several rings 28 are keyed as at 29 to the drum so that their respective hammer arms are in staggered relation to adjacent hammer arms. In its form shown herein, the several hammer arms produce a bit pattern on the surface of the drum, indicated diagrammatically in Figure 6.

Each of the hammer arms 25 consists of a Dick head 30, a shank 3i terminating in a pivot eye 32. Each hammer also has an integrally formed bit socket intermediate its ends. The bit sockets of the several hammers are arranged to support cutter bits 33 in different directions toward the outwardly facing side of the hammer arm. In the form shown herein, the three hammer arms in circumferential alignment about each ring 28 have their hit sockets disposed at three different angles, one socket 34 being centrally disposed, and the two other sockets 35 and 36 being arranged at equally inclined intermediate angles toward opposite sides of the hammer so that the bits in each row tend to cut a kerf 3i wider than the hammer shanks when the drum is rotated with the hammer arms pivotally swung into collapsed position toward the drum periphery, as indicated at A in Figure 2, in which position the bit 33 of the hammer arm is swung into a generally radial cutting position relative to the working face. Each of the rings 28 on which the hammer arms are pivotally mounted has an annular groove 33 in alignment with the shanks of their hammers, and said shank have stops as adapted to fit into the groove and engage the bottom thereof to limit the swinging movement of the hammer arms toward the drum axis, and to aid in providing lateral support for their cutter bits in cutting position when their respective hammer arms are in folded or collapsed positions toward the drum.

The pick heads 38 of the several hammer arms shown in Figures 1 to 4 are formed with laterally elongated chiselhaped impact picks or blades Ml projecting from their shanks on the same sides as the cutter bits 33. The striking edges of the blades may be tipped at ii with an abrasion resis-tant metal such as Stellite. Said striking edges are substantially longer than the width of the shanks 3| in a direction parallel with the axes of swinging movement of the hammers. When the hammer arms are in fully collapsed position, indicated at A in Figure 2, the tips of the striking surfaces it are retracted well below the arcuate paths of cutting movement of the cutter bits 33.

The heads 36! are substantially as wide, longitudinally of the drum, as the width of the kerf 3! cut by the cutter bits 33. Forward or counterclockwise pivotal movement of the hammer arms 25 is limited by overhanging surfaces 42 at opposite sides of the bit sockets 34, 35 and 36, and form stops engaging the proximate edges of the pivot lugs 27.

The modified form of hammer head shown in Figure has a widely tapered striking point 45.

The use and operation of the device is as follows:

It will be understood that the mining machine generally described hereinabove, upon which the novel cutting head is adapted for use, has means as usual for advancing or retracting the cutter head toward and away from the working face. and also for swinging the cutter head on an upright axis to position it at varying angles to the face as desired.

The cutter head Ill including the side bars I l, l l and drum 15 are bodily swung downwardly about horizontal axis 12 for removing a portion of the ci working face, as indicated diagrammatically in Figure 3. For this operation, the drum I5 is rotated in a counter-clockwise direction as seen in this figure.

When the cutter head is initially advanced toward the working face at the roof level, the several hammer arms will at first be relatively free to swing outwardly from the drum into a generally radial direction due to centrifugal force. As soon as the ends of the hammers engage the coal, they will first exert a series of successive blows on the face tending to fragment and dislodge the coal. As the forward or sumping movement is continued and the resistance of the coal increases, the ends of the hammer arms will be gradually swung pivotally toward the drum in a clockwise direction as the hammer arms successively engage the coal, until the cutter bits 33 assume a generally radial cutting position relative to the solid coal. The cutter bits will then tend to hold their respective hammer arms in collapsed position against their stops so as to out a series of parallel kerfs C lin the Working face, in a manner quite similar to cutter bits mounted in a conventional manner directly upon the periphery of a rotatable drum or cutter chain. It will be noted, however, that, as soon as the cutter bits 33, and the hammer heads 34 rotate beyond the zone of direct engagement with the coal face, the hammer is no longer confined by the latter, but is released so as to be swung outwardly on its pivotal axis into a generally radial position relative to the drum, as indicated at B in Figure 2.

Since each hammer is released from confinement at or near the top of the drum, it gathers momentum as it swings outwardly, and strikes the upstanding face of the coal, at the point indicated at X in Figure 2, with greatly augmented force, which is well below and beyond the area which is normally engaged by the cutter bits 33. As a result, the several hammer arms impart a series of successive blows upon the lip of solid coal immediately below and in the path of swinging movement of the drum, so as to break off and dislodge a substantial amount of coal in relatively large particle sizes from the solid face, before that area of the face is reached by the cutter bits.

As soon as the force of impact from each hammer arm has been delivered to the working face as described, the hammer arm will tend to rebound rearwardly in a clockwise direction, and at substantially the same time it will be advanced with the drum in a collapsed position into the coal face, so as to reengage its cutter bit 33 with the coal, so as to make another cut in its kerf 31. Such cutting action continues until the hammer arm is again released to an extended position for the next impact blow on the coal face below the drum.

It will be understood that the acceleration of pivotal movement of the hammer arms 25, so that they will strike the coal face with substantially maximum force, depends upon several factors, such as the relative length of the hammer arm and its point of pivotal connection to the drum axis, the peripheral speed of the drum, the swinging weight of the arm, the length of are through which the arm is permitted to swing freely, and the speed at which the drum is caused to traverse the face. It will also be found that the physical condition of the coal, as for instance if it is of a relatively friable or woody nature, will also have some effect upon the swinging action of the hammer arm. Accordingly, best results for different types and conditions of coal may require certain variations in controllable factors, such as the peripheral speed of the drum. For average conditions however, a drum with hammer arms pivoted on a diameter of approximately 12 inches, with hammer arms approximately 6 inches in effective length, and with the cutter bits being rotated at a peripheral speed of approximately 400-600 feet per minute, will give satisfactory results.

It will further be observed that, when the hammer arms are in collapsed position with their cutter bits 33 in cutting engagement with the coal, the wedged heads 40 at the ends of the arms are retracted radially so as to effect little, if any, cutting impression on the solid coal at the working face, yet said heads project radially from adjacent the periphery of the drum proper, in position to engage loose material dislodged by the cutter bits and carry it out of the space between the drum and working face for more or less forcible discharge rearwardly and downwardly as each hammer arm is released for swinging movement.

Although I have shown and described certain embodiments of my invention, it will be underclaim 1, wherein the drum is provided with a stood that I do not wish to be limited to the exact construction shown and described, but that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the appended claims.

I claim:

1. A cutting head for a mining machine comprising a drum rotatable by power, a plurality of elongated hammer arms pivotally mounted on circumferentially spaced axes about the periphcry of said drum, said hammer arms having pick heads at their outer ends, and cutter bits supported on and extending from intermediate their ends in the same general direction as said pick heads, each of said hammer arms having limited swingable movement from a radially extended position in which its pick head engages the working face, to a retracted position in engagement with the drum, in which its cutter bit is disposed in position to engage the working face on plurality of sets of hammer arms with each set of said hammers consisting of a plurality of hammers mounted in circumferentially spaced relation around the drum for swinging movement in substantially the same plane.

5. A cutting head structure in accordance with claim 4, wherein the hammer arms of each set have cutter bits disposed at varying divergent angles to their respective pick arms, to cut a widened kerf when said cutter bits are in retracted cutting position.

6. A cutting head structure in accordance with claim 5, wherein the pick heads are extended laterally so as to be substantially of the same width as the kerf cut by said cutter bits.

7. A cutting head structure in accordance with claim 4, wherein each set of hammer arms are pivotally mounted on a supporting ring which is detachably mounted on the drum.

8. A cutting head structure in accordance with claim 2, wherein the positive supporting means for each cutter bit includes laterally interfitting surfaces formed respectively on the periphery of the drum and the free end of the hammer arm on which said cutter bit is carried to restrain lateral movement of said arm when its bits are in retracted cutting position.

References Cited in the file of this patent FOREIGN PATENTS Number 

